blas_spermute(3P) Sun Performance Library blas_spermute(3P)NAMEblas_spermute - permutes a real array in terms of the permutation vec‐
tor P, output by dsortv
SYNOPSIS
SUBROUTINE BLAS_SPERMUTE (N, P, INCP, X, INCX)
INTEGER N
INTEGER P(*)
INTEGER INCP
REAL X(*)
INTEGER INCX
SUBROUTINE BLAS_SPERMUTE_64 (N, P, INCP, X, INCX)
INTEGER*8 N
INTEGER*8 P(*)
INTEGER*8 INCP
REAL X(*)
INTEGER*8 INCX
F95 INTERFACE
SUBROUTINE PERMUTE (X, P)
USE SUNPERF
SUBROUTINE PERMUTE_64 (X, P)
USE SUNPERF
ARGUMENTS
N (input) INTEGER, the number of elements to be permuted in X
If N <= 1, the subroutine returns without trying to permute
X.
P (input) INTEGER((N-1)*|INCP|+1), the permutation (index)
vector defined follows the same conventions as that for DTYPE
SORTV. It records the details of the interchanges of the ele‐
ments of X during sorting. That is X = P*X. In current imple‐
mentation, P contains the index of sorted X.
INCP (input) INTEGER, increment for P
INCP must not be zero. INCP could be negative. If INCP < 0,
the permutation is applied in the opposite direction. That
is
If INCP > 0,
if INCX > 0,
sorted X((i-1)*INCX+1) = X(P((i-1)*INCP+1)),
if INCX < 0,
sorted X((N-i)*|INCX|+1) = X(P((i-1)*INCP+1));
If INCP < 0,
if INCX > 0,
sorted X((i-1)*INCX+1) = X(P((N-i)*|INCP|+1)).
if INCX < 0,
sorted X((N-i)*|INCX|+1)
= X(P((N-i)*|INCP|+1)).
X (input/output) REAL(KIND)((N-1)*|INCX|+1), the array to be
permuted. Minimum size (N-1)*|INCX|+1 is required
INCX (input) INTEGER, increment for X
INCX must not be zero. INCX could be negative. If INCX < 0, X
will be permuted in a reverse way (see the description for
INCP above).
SEE ALSOblas_ssortv(3P), blas_ssort(3P)
6 Mar 2009 blas_spermute(3P)
